摘要
以仲丁醇铝、正硅酸乙酯为原料,制备了铝硅混合溶胶,干法拉丝制备了凝胶纤维,高温热解烧结得到莫来石纤维,研究了溶胶的稳定性以及热处理过程中相演变的过程.研究发现,加入乙酰乙酸乙酯,使其与铝离子螯合,可以有效防止铝溶胶的沉淀,显著改善溶胶的稳定性;聚乙烯吡咯烷酮(PVP)作为成纤助剂显著改善了溶胶的稳定性以及拉丝性能.FTIR、XRD、SEM、TG及DTA分析表明,利用该方法获得的溶胶属于单相溶胶.利用该溶胶制备的凝胶纤维在热处理过程中不形成氧化铝或者二氧化硅结晶相,而是在980℃直接形成莫来石,得到致密、细晶的莫来石纤维.
A stable alumina-silica sol had been prepared by using aluminum see-butoxide as the source of aluminum and partially hydrolyzed tetraethyl orthosilicate as the source of silicon. FTIR,XRD,SEM,TG and DTA were used to characterize the sol and examine the crystallographic and microstructure evolution of the dry-spun gel fibers during pyrolysis. It is found that ethyl acetoacetate （EAeAe） can effectively retard the precipitation in the sol by chelating with aluminum ions and significantly improve the stability of the sol. Polyvinylpyrrolidone （PVP） is compatible with the sol and has very positive effect on the dry-spinning ability of the spinning sol. No crystalline phases corresponding to alumina or silica have been found during pyrolysis before the formation of crystalline mullite phase at 980℃,indicating that the alumina-silica sol is mono-phasie. When the fiber was fired over 1 000℃ .dense mullite fibers were obtained.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2009年第4期610-612,共3页
Journal of Xiamen University：Natural Science
基金
福建省科技平台建设项目(2006L2003,2007H2004)
武器装备预研基金(9140A12050406QT87)项目资助
